P redictability is the most valuable currency of diplomacy. But it's been in decidedly short supply in Washington since Jan. 20, as the Trump administration meddles in foreign nations’ domestic politics with abandon.  This has made the job of many of the world's diplomats much harder, as they struggle to calibrate their country’s tone toward Washington while placating the steady churn of anxiety radiating from their bosses. Trade spats and tariff tiffs, reciprocity and revenge all are piling up